Wheeling register. [volume] (Wheeling, W. Va.) 1878-1935, 1887-10-25
A GREAT TEST.
LCoRiinued from Fourth Pdgs.

In yellow pine, stlcl; ID, the nails, which
were driven in rows across the stick,
showed decidedly greater resistance along
one edge over thu other, "a difference which
WAS also observed in the driving, and
those which drove the hardest gave TIE
highest adhesive resistance. In driving
nails Oblique 10 the direction in which they
will be pulled, some discretion has TO he
exercised The experiments with single
obhuucly driven DaIlS are nut favorable t"
this manner Of driving-ths nails bent
while they were being pulled, tore zap the
wood, and the friction against one face OF
the nail. the surface on the outside Of the
bend, must have been almost entirely re-
leased. Better results were obtained with
obliuue nails when used in Cleatsi here
| they showed greater resistance than nallS
perpendicular 10 the surface OF the c!eat,
although in each case the resistance Was
below corresponding results with single
uaiIS. Thus, clCats nailed to white pine
stick h, gave resistance OF 23S and 2SI
hounds per square inch, when the nails
we're driven perpendicular and obhqne 81 ,
respectively. Cleats on yellow pine, stick
| d, gave resistences of 1876 and 499 pounds
per suuare inch under the same conditions.
The taper of the nails, God were used,
driven 3 inches, was croSswise the grain OF
| the sticks.
Some nails and spikes we're driven in dry
wood, and then the pieces exposed alter
naTely to the tide water and air, and thus
| intermittiugly wet for a period OF Is days,
after which they were tested. The nails
were not rusty when drawn, although
| the wood was apparently water soaked as
deep as the nails were driven; 6Od. nails
were used and spikes which were 4" square
| by =" long, each were driven ~ into the
wood. In white pine, stick b, the nails
showed 1879 pounds per square inch, the
spikes 23l pounds per square inch resist
ance. In yellow pine, stick ID, the nails
gave ass pounds per square inch the spikes
| gg6 pounds per square inch resistance.
In white oak, stick +, the nails gave $50
pounds per square inch, the spikes as
pounds per square inch resistance. II vii!
| he seen that all of these results, with wet
sticks are below the corresponding resist
ances with dry wood
A number OF experiments were made on
| the resistance Of driving sod. nails per
| pendicular to the grain, THESE tests we're
made by slowly driving the nails with hy-
draulic power, and noting the force re,
uuired. The maximum resistance to driy'
| lng in white pine, stick b, Was 39l pounds
| pcr suuare inch when the nails were driven
! 81, and 397 pounds per square inch when
\ they were driven ~. In yellow pines,
stick ID, the resiStanees were 572 pounds
per square inch, ami 635 pounds per square
| inch for 81 and 1" depth OF nail, 1t Was
observed that the resistance to penetration
| was not uniform, but varied as different
LAYERS OF the wood were reached; az times
the nails would continue 10 penetrate the
wood under less load than had previous
| IL been resisted, this variation being from
! , To 10 per cent OF the load. These
/ experiments were few, and as there
were no observations on pulling The
same nails, a comparison of the resist
auces in the two directions cannot we'll bI
made, il is obvious, however, that the re
sistauce to driving must be exceptionally
low in the yellow pine. The resistance Il
driving probably does not differ very mucl
from the resistance TO pulling, except ST
far as belongs to the displacement of fiber
DN the point el TUG iidh NhiCu ~ SuOouuI
cred in che one ease, but not the other
aud the proportion which that Resistance
would bear to the whole should dlminisl
~ the nail l. driven aud the frictional sur
face in the wood increases. The yieldiD:
ut the tibers under high cOmpreSsive load'
HTS been referred to, and that behaviOl
would cause somewhat greater resistance
to driving than to pulling, provided some
time elapsed between the two operations